Fineness of ink (below)

Squeegee squeegee should be scraped off vertically. This is only visually vertical. There is always a certain amount of error in the specific operation. The ideal edge of the scraper is ground into a 15 degree arc to avoid this error. In general, the smaller the arc, the finer the sharper knife scraped, and vice versa. .
The ink industry has high requirements on the accuracy of the scraper, and the scraper and scraper can cause measurement errors. How can you come to an accurate test result? We can use the matching method to solve this problem.
The scraper with a high micron number matches the scraper with a small curvature.
The micron-sized scraper matches the oversized scraper.
The matched scraper fineness meter is calibrated with the company's quality inspection center and verified by the national metrological verification laboratory. If not, replace the scraper or scraper until it is suitable.
If it is equipped with a squeegee technology, it can also use a squeegee to make the comparative screed fineness meter and the standard screed fineness meter have substantially the same fineness value.
Second, the impact of the use of tools and equipment 1. Ink knife ink knife plane should be smooth, it is best to use rolling, polished, rough surface of the knife will retain ink, and the other knife is best ground into a knife blade angle of 30 to 40 degrees , Flatness ≤ 1μm, such a blade can scrape ink on the glass plate, wipe clean every time.
2. The wiper wiper should be wiped before every use. During the operation, it should be wiped. Generally, a small amount of solvent is used in the soft cotton yarn. If the cotton yarn is not clean, leaving dust or hair loss will affect the test results. The existing industrial paper is used. This paper solvent wipe can avoid this problem.
3. Dilution Oil No. 6 with No. 6 oil is used as dilution oil for offset printing inks. It is currently necessary to use filter paper to filter fineness ≤ 7.5 μm to remove mechanical impurities. If the No. 6 oil is only thickened due to slight polymerization, it can be heated to achieve the fineness requirements. Imagine if the No. 6 oil itself is thick, then can you judge the ink fineness? You can prepare a vial for use during your spare time.
Third, the impact of the operation mode 1. Take ink-like offset printing ink surface layer due to oxidation and conjunctiva, when taking ink should first remove the surface dry skin, take four positions of the ink, so that it is representative. The ink was taken 15 times on a glass plate, and the round trip was once. Take a small part of it, such as 0.3ml each.
2. Dilute with No. 6 oil to determine the amount of oil based on the fluidity of the ink. It should be noted that the oil should not be added all at once. If you add ink blocks at a time, they will look like large particles. In addition, when the ink is basically adjusted, the knife should be wiped and adjusted again. This is especially important for red ink and blue ink. There are uncoordinated inks on the blade that are large particles. , screening test results.
3. The scraper should be as vertical as possible when scraping ink. When the knife is tilted backward, the fineness is small (thin), and when it is tilted forward, the fineness is larger (thick). When wiping the ink, use both hands to use the knife evenly and do not emphasize one side.
4. After wiping the ink, the surface of the squeegee should be observed obliquely at a 30-degree angle to the light source. Within 30 seconds, the number of particles in a scale range at the focal point and the concentration point should be quickly determined to determine the fineness value. The observation must be fast and accurate.
5. For an ink, if the item to be measured is not an item, first measure the fineness so as not to contaminate the ink when measuring other items. Measure the fineness, scrape the color film and measure the coloring force, and then do other projects.
Fourth, other influencing factors The fineness of the environment to be tested should be kept free of dust, and accessories such as cotton yarn should be prepared in advance and the solvents should be filtered. The ambient temperature should not be too low. It is customary to say that the detection fineness is not related to temperature and humidity. It is best to test under standard conditions of temperature and humidity.
2. The light source for observing the fineness is preferably a standard light source. If the conditions are not met, the brightness of the light source should be appropriate and a magnifying glass should be used for observation.